The central bank scrapped about 15 deduction rules, many established during the 2008 global financial crisis, to simplify the process for banks as well as to unify calculation periods for term, demand and savings deposits.

The government of President Michel Temer has announced a series of microeconomic measures to reduce the debt burden of consumers struggling to pay their bills after two years of recession.

"We are working to create a more positive macroeconomic environment that in time will reduce credit costs," central bank Monetary Policy Director Reinaldo Le Grazie told reporters, adding that the bank cannot estimate how much the banks will save with the measure. "We can't do magic."

In December, central bank Governor Ilan Goldfajn announced the creation of a mechanism in which the bank pays interest on excess reserves kept at the bank to increase the efficiency of monetary policy.

Under Goldfajn, the bank has stepped up monetary easing, cutting its benchmark Selic rate by a whopping 75 basis points to 13 percent at its last meeting on Jan. 11.

Goldfajn has also vowed to look for ways to reduce the interest rates charged by credit card companies, which at times top 400 percent a year in Brazil.

Reserve requirements are monetary policy tools in which commercial banks are forced to keep part of their reserves at the central bank to control the volume of money in the economy. (Reporting by Alonso Soto and Silvio Cascione; Editing by Chris Reese and Alan Crosby)